From: Brian Aker <brian@tangent.org>
Date: Tue, 6 Jan 2009 22:08:04 +0000 (-0800)
Subject: Import new purge work from trond
X-Git-Tag: 0.26~27
X-Git-Url: https://git.m6w6.name/?a=commitdiff_plain;h=6b020861bcd821c005e218f45d9c6cea8a9d0947;hp=69d1480282790f15a2e200444c619c539b0fe078;p=awesomized%2Flibmemcached

Import new purge work from trond
---

diff --git a/ChangeLog b/ChangeLog
index 8ff99b09..ba1964db 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,6 +1,7 @@
 0.26
   * Fix for decrement on hash key
   * Fixed assert that was catching bad memset() call in host_reset()
+  * Fix purge issue for blocked IO which has been stacked.
 
 0.25 Fri Nov 28 09:59:35 PST 2008
   * Jenkins HASH added.
diff --git a/libmemcached/memcached_io.c b/libmemcached/memcached_io.c
index 6f852893..9a11556b 100644
--- a/libmemcached/memcached_io.c
+++ b/libmemcached/memcached_io.c
@@ -30,7 +30,6 @@ static memcached_return io_wait(memcached_server_st *ptr,
   fds[0].fd= ptr->fd;
   fds[0].events= flags;
 
-#ifdef NOT_DONE
   /*
   ** We are going to block on write, but at least on Solaris we might block
   ** on write if we haven't read anything from our input buffer..
@@ -41,10 +40,10 @@ static memcached_return io_wait(memcached_server_st *ptr,
   */
   if (read_or_write == MEM_WRITE)
   {
-    if (memcached_purge(ptr) != MEMCACHED_SUCCESS || memcached_purge(ptr) != MEMCACHED_STORED)
-      return MEMCACHED_FAILURE;
+    memcached_return rc=memcached_purge(ptr);
+    if (rc != MEMCACHED_SUCCESS && rc != MEMCACHED_STORED)
+       return MEMCACHED_FAILURE;
   }
-#endif
 
   error= poll(fds, 1, ptr->root->poll_timeout);
 
@@ -216,7 +215,9 @@ ssize_t memcached_io_write(memcached_server_st *ptr,
       if (sent_length == -1)
         return -1;
 
-      WATCHPOINT_ASSERT(sent_length == MEMCACHED_MAX_BUFFER);
+      /* If io_flush calls memcached_purge, sent_length may be 0 */
+      if (sent_length != 0)
+        WATCHPOINT_ASSERT(sent_length == MEMCACHED_MAX_BUFFER);
     }
   }
 
@@ -265,6 +266,19 @@ memcached_return memcached_io_close(memcached_server_st *ptr)
 static ssize_t io_flush(memcached_server_st *ptr,
                         memcached_return *error)
 {
+  /*
+  ** We might want to purge the input buffer if we haven't consumed
+  ** any output yet... The test for the limits is the purge is inline
+  ** in the purge function to avoid duplicating the logic..
+  */
+  {
+     memcached_return rc;
+     WATCHPOINT_ASSERT(ptr->fd != -1);
+     rc= memcached_purge(ptr);
+
+     if (rc != MEMCACHED_SUCCESS && rc != MEMCACHED_STORED)
+       return -1;
+  }
   ssize_t sent_length;
   size_t return_length;
   char *local_write_ptr= ptr->write_buffer;
@@ -320,22 +334,6 @@ static ssize_t io_flush(memcached_server_st *ptr,
     }
     else
     {
-#ifdef NOT_DONE
-      /*
-      ** We might want to purge the input buffer if we haven't consumed
-      ** any output yet... The test for the limits is the purge is inline
-      ** in the purge function to avoid duplicating the logic..
-      */
-      {
-        memcached_return rc;
-        WATCHPOINT_ASSERT(ptr->fd != -1);
-        rc= memcached_purge(ptr);
-
-        if (rc != MEMCACHED_SUCCESS || rc != MEMCACHED_STORED)
-          return -1;
-      }
-#endif
-
       WATCHPOINT_ASSERT(ptr->fd != -1);
       if ((sent_length= write(ptr->fd, local_write_ptr, 
                               write_length)) == -1)
@@ -349,7 +347,7 @@ static ssize_t io_flush(memcached_server_st *ptr,
             memcached_return rc;
             rc= io_wait(ptr, MEM_WRITE);
 
-            if (rc == MEMCACHED_SUCCESS)
+            if (rc == MEMCACHED_SUCCESS || rc == MEMCACHED_TIMEOUT) 
               continue;
 
             memcached_quit_server(ptr, 1);
@@ -386,3 +384,28 @@ void memcached_io_reset(memcached_server_st *ptr)
 {
   memcached_quit_server(ptr, 1);
 }
+
+/**
+ * Read a given number of bytes from the server and place it into a specific
+ * buffer. Reset the IO channel on this server if an error occurs. 
+ */
+memcached_return memcached_safe_read(memcached_server_st *ptr,
+                                     void *dta,
+                                     size_t size)
+{
+  size_t offset= 0;
+  char *data= dta;
+
+  while (offset < size)
+  {
+    ssize_t nread= memcached_io_read(ptr, data + offset, size - offset);
+    if (nread <= 0)
+    {
+      memcached_io_reset(ptr);
+      return MEMCACHED_UNKNOWN_READ_FAILURE;
+    }
+    offset+= nread;
+  }
+
+  return MEMCACHED_SUCCESS;
+}
diff --git a/libmemcached/memcached_io.h b/libmemcached/memcached_io.h
index 8361a577..3da8af75 100644
--- a/libmemcached/memcached_io.h
+++ b/libmemcached/memcached_io.h
@@ -10,4 +10,12 @@ void memcached_io_reset(memcached_server_st *ptr);
 ssize_t memcached_io_read(memcached_server_st *ptr,
                           void *buffer, size_t length);
 memcached_return memcached_io_close(memcached_server_st *ptr);
+/* Read n bytes of data from the server and store them in dta */
+memcached_return memcached_safe_read(memcached_server_st *ptr, 
+                                     void *dta, 
+                                     size_t size);
+/* Read a single response from the server */
+memcached_return memcached_read_one_response(memcached_server_st *ptr,
+                                             char *buffer, size_t buffer_length,
+                                             memcached_result_st *result);
 #endif /* __MEMCACHED_IO_H__ */
diff --git a/libmemcached/memcached_purge.c b/libmemcached/memcached_purge.c
index c73e97ff..96bf1d27 100644
--- a/libmemcached/memcached_purge.c
+++ b/libmemcached/memcached_purge.c
@@ -1,21 +1,17 @@
-#include <assert.h>
-
 #include "common.h"
 #include "memcached_io.h"
+#include "memcached_constants.h"
 
-memcached_return memcached_purge(memcached_server_st *ptr) 
+memcached_return memcached_purge(memcached_server_st *ptr)
 {
-  memcached_return rc;
-  int32_t timeout;
-  char buffer[2048];
-  memcached_result_st result;
-  memcached_result_st *result_ptr;
+  uint32_t x;
+  memcached_return ret= MEMCACHED_SUCCESS;
 
   if (ptr->root->purging || /* already purging */
-      (memcached_server_response_count(ptr) < ptr->root->io_msg_watermark && 
-       ptr->io_bytes_sent < ptr->root->io_bytes_watermark) ||
-      (ptr->io_bytes_sent > ptr->root->io_bytes_watermark && 
-       memcached_server_response_count(ptr) < 10)) 
+      (memcached_server_response_count(ptr) < ptr->root->io_msg_watermark &&
+      ptr->io_bytes_sent < ptr->root->io_bytes_watermark) ||
+      (ptr->io_bytes_sent > ptr->root->io_bytes_watermark &&
+      memcached_server_response_count(ptr) < 2))
   {
     return MEMCACHED_SUCCESS;
   }
@@ -28,33 +24,53 @@ memcached_return memcached_purge(memcached_server_st *ptr)
   /* Force a flush of the buffer to ensure that we don't have the n-1 pending
      requests buffered up.. */
   if (memcached_io_write(ptr, NULL, 0, 1) == -1)
-    return MEMCACHED_FAILURE;
+  {
+    ptr->root->purging= 0;
+    return MEMCACHED_WRITE_FAILURE;
+  }
   WATCHPOINT_ASSERT(ptr->fd != -1);
 
-  /* we have already incremented the response counter, and memcached_response
-     will read out all messages.. To avoid memcached_response to wait forever
-     for a response to a command I have in my buffer, let's decrement the 
-     response counter :) */
-  memcached_server_response_decrement(ptr);
-  
-  /* memcached_response may call memcached_io_read, but let's use a short
-     timeout if there is no data yet */
-  timeout= ptr->root->poll_timeout;
-  ptr->root->poll_timeout= 1;
-  result_ptr= memcached_result_create(ptr->root, &result);
-
-  if (result_ptr == NULL)
-    return MEMCACHED_FAILURE;
+  int no_msg= memcached_server_response_count(ptr) - 1;
+  if (no_msg > 0)
+  {
+    memcached_result_st result;
+    memcached_result_st *result_ptr;
+    char buffer[SMALL_STRING_LEN];
 
-  WATCHPOINT_ASSERT(ptr->fd != -1);
-  rc= memcached_response(ptr, buffer, sizeof(buffer), &result);
-  WATCHPOINT_ERROR(rc);
-  WATCHPOINT_ASSERT(ptr->fd != -1);
-  ptr->root->poll_timeout= timeout;
-  memcached_server_response_increment(ptr);
-  ptr->root->purging = 0;
+    /*
+     * We need to increase the timeout, because we might be waiting for
+     * data to be sent from the server (the commands was in the output buffer
+     * and just flushed
+     */
+    long timeo= ptr->root->poll_timeout;
+    ptr->root->poll_timeout= 2000;
+
+    result_ptr= memcached_result_create(ptr->root, &result);
+    WATCHPOINT_ASSERT(result_ptr);
 
-  memcached_result_free(&result);
+    for (x= 0; x < no_msg; x++)
+    {
+      memcached_result_reset(result_ptr);
+      memcached_return rc= memcached_read_one_response(ptr, buffer,
+                                                       sizeof (buffer),
+                                                       result_ptr);
+      /*
+       * Purge doesn't care for what kind of command results that is received.
+       * The only kind of errors I care about if is I'm out of sync with the
+       * protocol or have problems reading data from the network..
+       */
+      if (rc== MEMCACHED_PROTOCOL_ERROR || rc == MEMCACHED_UNKNOWN_READ_FAILURE)
+      {
+        WATCHPOINT_ERROR(rc);
+        ret = rc;
+        memcached_io_reset(ptr);
+      }
+    }
+
+    memcached_result_free(result_ptr);
+    ptr->root->poll_timeout=timeo;
+  }
+  ptr->root->purging= 0;
 
-  return rc;
+  return ret;
 }
diff --git a/libmemcached/memcached_response.c b/libmemcached/memcached_response.c
index 3a071c14..5c44e5f2 100644
--- a/libmemcached/memcached_response.c
+++ b/libmemcached/memcached_response.c
@@ -8,79 +8,102 @@
 #include "common.h"
 #include "memcached_io.h"
 
-static memcached_return binary_response(memcached_server_st *ptr, 
-                                        char *buffer, size_t buffer_length,
-                                        memcached_result_st *result);
-
-memcached_return memcached_response(memcached_server_st *ptr, 
-                                    char *buffer, size_t buffer_length,
-                                    memcached_result_st *result)
+static memcached_return textual_read_one_response(memcached_server_st *ptr,
+                                                  char *buffer, size_t buffer_length,
+                                                  memcached_result_st *result);
+static memcached_return binary_read_one_response(memcached_server_st *ptr,
+                                                 char *buffer, size_t buffer_length,
+                                                 memcached_result_st *result);
+
+memcached_return memcached_read_one_response(memcached_server_st *ptr,
+                                             char *buffer, size_t buffer_length,
+                                             memcached_result_st *result)
 {
-  unsigned int x;
-  size_t send_length;
-  char *buffer_ptr;
-  unsigned int max_messages;
-
+  memcached_server_response_decrement(ptr);
 
-  send_length= 0;
-  /* UDP at the moment is odd...*/
-  if (ptr->type == MEMCACHED_CONNECTION_UDP)
-  {
-    char buffer[8];
-    ssize_t read_length;
+  memcached_return rc;
+  if (ptr->root->flags & MEM_BINARY_PROTOCOL)
+    rc= binary_read_one_response(ptr, buffer, buffer_length, result);
+  else
+    rc= textual_read_one_response(ptr, buffer, buffer_length, result);
 
-    return MEMCACHED_SUCCESS;
+  unlikely(rc == MEMCACHED_UNKNOWN_READ_FAILURE ||
+           rc == MEMCACHED_PROTOCOL_ERROR ||
+           rc == MEMCACHED_CLIENT_ERROR ||
+           rc == MEMCACHED_MEMORY_ALLOCATION_FAILURE)
+     memcached_io_reset(ptr);
 
-    read_length= memcached_io_read(ptr, buffer, 8);
-  }
+  return rc;
+}
 
+memcached_return memcached_response(memcached_server_st *ptr, 
+                                    char *buffer, size_t buffer_length,
+                                    memcached_result_st *result)
+{
   /* We may have old commands in the buffer not set, first purge */
   if (ptr->root->flags & MEM_NO_BLOCK)
     (void)memcached_io_write(ptr, NULL, 0, 1);
 
-  if (ptr->root->flags & MEM_BINARY_PROTOCOL)
-    return binary_response(ptr, buffer, buffer_length, result);
-  
-  max_messages= memcached_server_response_count(ptr);
-  for (x= 0; x <  max_messages; x++)
-  {
-    size_t total_length= 0;
-    buffer_ptr= buffer;
-
-
-    while (1)
-    {
-      ssize_t read_length;
-
-      read_length= memcached_io_read(ptr, buffer_ptr, 1);
-      WATCHPOINT_ASSERT(*buffer_ptr != '\0');
+  /*
+   * The previous implementation purged all pending requests and just
+   * returned the last one. Purge all pending messages to ensure backwards
+   * compatibility. 
+   */
+  if ((ptr->root->flags & MEM_BINARY_PROTOCOL) == 0)
+    while (memcached_server_response_count(ptr) > 1) {
+      memcached_return rc= memcached_read_one_response(ptr, buffer, buffer_length, result);
+      
+      unlikely (rc != MEMCACHED_END &&
+                rc != MEMCACHED_STORED &&
+                rc != MEMCACHED_SUCCESS &&
+                rc != MEMCACHED_STAT && 
+                rc != MEMCACHED_DELETED &&
+                rc != MEMCACHED_NOTFOUND &&
+                rc != MEMCACHED_NOTSTORED && 
+                rc != MEMCACHED_DATA_EXISTS)
+	return rc;
+    }
 
-      if (read_length != 1)
-      {
-        memcached_io_reset(ptr);
-        return  MEMCACHED_UNKNOWN_READ_FAILURE;
-      }
+  return memcached_read_one_response(ptr, buffer, buffer_length, result);
+}
 
-      if (*buffer_ptr == '\n')
-        break;
-      else
-        buffer_ptr++;
+static memcached_return memcached_readline(memcached_server_st *ptr,
+                                           char *buffer,
+                                           size_t size)
+{
+  bool line_complete= false;
+  char *buffer_ptr= buffer;
+  int total_nr=0;
 
-      total_length++;
-      WATCHPOINT_ASSERT(total_length <= buffer_length);
+  while (!line_complete)
+  {
+    if (memcached_io_read(ptr, buffer_ptr, 1) != 1)
+      return MEMCACHED_UNKNOWN_READ_FAILURE;
 
-      if (total_length >= buffer_length)
-      {
-        memcached_io_reset(ptr);
-        return MEMCACHED_UNKNOWN_READ_FAILURE;
-      }
+    WATCHPOINT_ASSERT(*buffer_ptr != '\0');
+    if (*buffer_ptr == '\n')
+      line_complete=true;
+    else
+    {
+      ++buffer_ptr;
+      ++total_nr;
     }
-    buffer_ptr++;
-    *buffer_ptr= 0;
 
-    memcached_server_response_decrement(ptr);
+    if (total_nr == size)
+      return MEMCACHED_PROTOCOL_ERROR;
   }
 
+  return MEMCACHED_SUCCESS;
+}
+
+static memcached_return textual_read_one_response(memcached_server_st *ptr,
+                                                  char *buffer, size_t buffer_length,
+                                                  memcached_result_st *result)
+{
+  memcached_return rc=memcached_readline(ptr, buffer, buffer_length);
+  if (rc != MEMCACHED_SUCCESS)
+    return rc;
+
   switch(buffer[0])
   {
   case 'V': /* VALUE || VERSION */
@@ -105,7 +128,6 @@ memcached_return memcached_response(memcached_server_st *ptr,
     {
       WATCHPOINT_STRING(buffer);
       WATCHPOINT_ASSERT(0);
-      memcached_io_reset(ptr);
       return MEMCACHED_UNKNOWN_READ_FAILURE;
     }
   case 'O': /* OK */
@@ -125,7 +147,6 @@ memcached_return memcached_response(memcached_server_st *ptr,
       {
         WATCHPOINT_STRING(buffer);
         WATCHPOINT_ASSERT(0);
-        memcached_io_reset(ptr);
         return MEMCACHED_UNKNOWN_READ_FAILURE;
       }
     }
@@ -138,45 +159,30 @@ memcached_return memcached_response(memcached_server_st *ptr,
       else if (buffer[4] == 'S')
         return MEMCACHED_NOTSTORED;
       else
-      {
-        memcached_io_reset(ptr);
         return MEMCACHED_UNKNOWN_READ_FAILURE;
-      }
     }
   case 'E': /* PROTOCOL ERROR or END */
     {
       if (buffer[1] == 'N')
         return MEMCACHED_END;
       else if (buffer[1] == 'R')
-      {
-        memcached_io_reset(ptr);
         return MEMCACHED_PROTOCOL_ERROR;
-      }
       else if (buffer[1] == 'X')
-      {
         return MEMCACHED_DATA_EXISTS;
-      }
       else
-      {
-        memcached_io_reset(ptr);
         return MEMCACHED_UNKNOWN_READ_FAILURE;
-      }
     }
   case 'C': /* CLIENT ERROR */
-    memcached_io_reset(ptr);
     return MEMCACHED_CLIENT_ERROR;
   default:
     {
       unsigned long long auto_return_value;
 
-      if (sscanf(buffer, "%llu", &auto_return_value) == 1) 
+      if (sscanf(buffer, "%llu", &auto_return_value) == 1)
         return MEMCACHED_SUCCESS;
 
-      memcached_io_reset(ptr);
-
       return MEMCACHED_UNKNOWN_READ_FAILURE;
     }
-
   }
 
   return MEMCACHED_SUCCESS;
@@ -194,47 +200,18 @@ size_t memcached_result_length(memcached_result_st *ptr)
   return memcached_string_length(sptr);
 }
 
-/**
- * Read a given number of bytes from the server and place it into a specific
- * buffer. Reset the IO channel or this server if an error occurs. 
- */
-static memcached_return safe_read(memcached_server_st *ptr, void *dta, 
-                                  size_t size) 
-{
-  size_t offset= 0;
-  char *data= dta;
-
-  while (offset < size) 
-  {
-    ssize_t nread= memcached_io_read(ptr, data + offset, size - offset);
-    if (nread <= 0) 
-    {
-      memcached_io_reset(ptr);
-      return MEMCACHED_UNKNOWN_READ_FAILURE;
-    }
-    offset += nread;
-  }
-   
-  return MEMCACHED_SUCCESS;
-}
-
-static memcached_return binary_response(memcached_server_st *ptr,
-                                        char *buffer,
-                                        size_t buffer_length,
-                                        memcached_result_st *result) 
+static memcached_return binary_read_one_response(memcached_server_st *ptr,
+                                                 char *buffer, size_t buffer_length,
+                                                 memcached_result_st *result)
 {
   protocol_binary_response_header header;
-  memcached_server_response_decrement(ptr);
    
-  unlikely (safe_read(ptr, &header.bytes, 
-                      sizeof(header.bytes)) != MEMCACHED_SUCCESS)
+  unlikely (memcached_safe_read(ptr, &header.bytes, 
+                                sizeof(header.bytes)) != MEMCACHED_SUCCESS)
     return MEMCACHED_UNKNOWN_READ_FAILURE;
 
   unlikely (header.response.magic != PROTOCOL_BINARY_RES) 
-  {
-    memcached_io_reset(ptr);
     return MEMCACHED_PROTOCOL_ERROR;
-  }
 
   /*
   ** Convert the header to host local endian!
@@ -256,33 +233,25 @@ static memcached_return binary_response(memcached_server_st *ptr,
         memcached_result_reset(result);
         result->cas= header.response.cas;
 
-        if (safe_read(ptr, &result->flags,
-                      sizeof(result->flags)) != MEMCACHED_SUCCESS) 
-        {
+        if (memcached_safe_read(ptr, &result->flags,
+                                sizeof (result->flags)) != MEMCACHED_SUCCESS)
           return MEMCACHED_UNKNOWN_READ_FAILURE;
-        }
+
         result->flags= ntohl(result->flags);
         bodylen -= header.response.extlen;
 
         result->key_length= keylen;
-        if (safe_read(ptr, result->key, keylen) != MEMCACHED_SUCCESS) 
-        {
+        if (memcached_safe_read(ptr, result->key, keylen) != MEMCACHED_SUCCESS) 
           return MEMCACHED_UNKNOWN_READ_FAILURE;
-        }
 
         bodylen -= keylen;
         if (memcached_string_check(&result->value,
                                    bodylen) != MEMCACHED_SUCCESS) 
-        {
-          memcached_io_reset(ptr);
           return MEMCACHED_MEMORY_ALLOCATION_FAILURE;
-        }
 
         char *vptr= memcached_string_value(&result->value);
-        if (safe_read(ptr, vptr, bodylen) != MEMCACHED_SUCCESS) 
-        {
+        if (memcached_safe_read(ptr, vptr, bodylen) != MEMCACHED_SUCCESS) 
           return MEMCACHED_UNKNOWN_READ_FAILURE;
-        }
 
         memcached_string_set_length(&result->value, bodylen);  
       } 
@@ -291,16 +260,12 @@ static memcached_return binary_response(memcached_server_st *ptr,
     case PROTOCOL_BINARY_CMD_DECREMENT:
       {
         if (bodylen != sizeof(uint64_t) || buffer_length != sizeof(uint64_t)) 
-        {
           return MEMCACHED_PROTOCOL_ERROR;
-        }
 
         WATCHPOINT_ASSERT(bodylen == buffer_length);
         uint64_t val;
-        if (safe_read(ptr, &val, sizeof(val)) != MEMCACHED_SUCCESS) 
-        {
+        if (memcached_safe_read(ptr, &val, sizeof(val)) != MEMCACHED_SUCCESS) 
           return MEMCACHED_UNKNOWN_READ_FAILURE;
-        }
 
         val= ntohll(val);
         memcpy(buffer, &val, sizeof(val));
@@ -312,8 +277,8 @@ static memcached_return binary_response(memcached_server_st *ptr,
         if (bodylen >= buffer_length)
           /* not enough space in buffer.. should not happen... */
           return MEMCACHED_UNKNOWN_READ_FAILURE;
-        else 
-          safe_read(ptr, buffer, bodylen);
+        else if (memcached_safe_read(ptr, buffer, bodylen) != MEMCACHED_SUCCESS)
+          return MEMCACHED_UNKNOWN_READ_FAILURE;
       } 
       break;
     case PROTOCOL_BINARY_CMD_FLUSH:
@@ -346,8 +311,10 @@ static memcached_return binary_response(memcached_server_st *ptr,
         {
           size_t keylen= header.response.keylen;            
           memset(buffer, 0, buffer_length);
-          safe_read(ptr, buffer, keylen);
-          safe_read(ptr, buffer + keylen + 1, bodylen - keylen);
+          if (memcached_safe_read(ptr, buffer, keylen) != MEMCACHED_SUCCESS ||
+              memcached_safe_read(ptr, buffer + keylen + 1, 
+                                  bodylen - keylen) != MEMCACHED_SUCCESS)
+            return MEMCACHED_UNKNOWN_READ_FAILURE;
         }
       } 
       break;
@@ -355,7 +322,6 @@ static memcached_return binary_response(memcached_server_st *ptr,
       {
         /* Command not implemented yet! */
         WATCHPOINT_ASSERT(0);
-        memcached_io_reset(ptr);
         return MEMCACHED_PROTOCOL_ERROR;
       }        
     }
@@ -367,7 +333,8 @@ static memcached_return binary_response(memcached_server_st *ptr,
     while (bodylen > 0) 
     {
       size_t nr= (bodylen > SMALL_STRING_LEN) ? SMALL_STRING_LEN : bodylen;
-      safe_read(ptr, buffer, nr);
+      if (memcached_safe_read(ptr, buffer, nr) != MEMCACHED_SUCCESS)
+        return MEMCACHED_UNKNOWN_READ_FAILURE;
       bodylen -= nr;
     }
   }
diff --git a/tests/function.c b/tests/function.c
index ab6d4567..7ec22d4c 100644
--- a/tests/function.c
+++ b/tests/function.c
@@ -395,10 +395,13 @@ static test_return  cas2_test(memcached_st *memc)
 static test_return  cas_test(memcached_st *memc)
 {
   memcached_return rc;
-  char *key= "fun";
-  size_t key_length= strlen("fun");
-  char *value= "we the people";
-  size_t value_length= strlen("we the people");
+  const char *key= "fun";
+  size_t key_length= strlen(key);
+  const char *value= "we the people";
+  size_t value_length= strlen(value);
+  const char *value2= "change the value";
+  size_t value2_length= strlen(value2);
+
   memcached_result_st results_obj;
   memcached_result_st *results;
   unsigned int set= 1;
@@ -421,24 +424,27 @@ static test_return  cas_test(memcached_st *memc)
   assert(results);
   assert(rc == MEMCACHED_SUCCESS);
   WATCHPOINT_ASSERT(memcached_result_cas(results));
-
-  assert(!memcmp(value, "we the people", strlen("we the people")));
-  assert(strlen("we the people") == value_length);
+  assert(!memcmp(value, memcached_result_value(results), value_length));
+  assert(strlen(memcached_result_value(results)) == value_length);
   assert(rc == MEMCACHED_SUCCESS);
+  uint64_t cas = memcached_result_cas(results);
 
-  rc= memcached_cas(memc, key, key_length,
-                    "change the value", strlen("change the value"), 
-                    0, 0, memcached_result_cas(results));
-
+  #if 0
+  results= memcached_fetch_result(memc, &results_obj, &rc);
+  assert(rc == MEMCACHED_END);
+  assert(results == NULL);
+#endif
+  
+  rc= memcached_cas(memc, key, key_length, value2, value2_length, 0, 0, cas);
   assert(rc == MEMCACHED_SUCCESS);
 
-  rc= memcached_cas(memc, key, key_length,
-                    "change the value", strlen("change the value"), 
-                    0, 0, 23);
-
+  /*
+   * The item will have a new cas value, so try to set it again with the old
+   * value. This should fail!
+   */
+  rc= memcached_cas(memc, key, key_length, value2, value2_length, 0, 0, cas);
   assert(rc == MEMCACHED_DATA_EXISTS);
 
-
   memcached_result_free(&results_obj);
 
   return 0;
@@ -1397,13 +1403,11 @@ static test_return  user_supplied_bug1(memcached_st *memc)
     sprintf(key, "%d", x);
     rc = memcached_set(memc, key, strlen(key), 
                        randomstuff, strlen(randomstuff), 10, 0);
-    WATCHPOINT_ERROR(rc);
     assert(rc == MEMCACHED_SUCCESS || rc == MEMCACHED_BUFFERED);
     /* If we fail, lets try again */
     if (rc != MEMCACHED_SUCCESS && rc != MEMCACHED_BUFFERED)
       rc = memcached_set(memc, key, strlen(key), 
                          randomstuff, strlen(randomstuff), 10, 0);
-    WATCHPOINT_ERROR(rc);
     assert(rc == MEMCACHED_SUCCESS || rc == MEMCACHED_BUFFERED);
   }
 
@@ -1931,7 +1935,11 @@ static test_return  user_supplied_bug12(memcached_st *memc)
                           1, &number_value);
 
   assert(value == NULL);
-  assert(rc == MEMCACHED_NOTFOUND);
+  /* The binary protocol will set the key if it doesn't exist */
+  if (memcached_behavior_get(memc, MEMCACHED_BEHAVIOR_BINARY_PROTOCOL) == 1) 
+    assert(rc == MEMCACHED_SUCCESS);
+  else
+    assert(rc == MEMCACHED_NOTFOUND);
 
   rc= memcached_set(memc, "autoincrement", strlen("autoincrement"), "1", 1, 0, 0);
 
@@ -2150,6 +2158,33 @@ test_return user_supplied_bug19(memcached_st *memc)
   return 0;
 }
 
+/* CAS test from Andei */
+test_return user_supplied_bug20(memcached_st *memc)
+{
+  memcached_return status;
+  memcached_result_st *result, result_obj;
+  char *key = "abc";
+  size_t key_len = strlen("abc");
+  char *value = "foobar";
+  size_t value_len = strlen(value);
+
+  memcached_behavior_set(memc, MEMCACHED_BEHAVIOR_SUPPORT_CAS, 1);
+
+  status = memcached_set(memc, key, key_len, value, value_len, (time_t)0, (uint32_t)0);
+  assert(status == MEMCACHED_SUCCESS);
+
+  status = memcached_mget(memc, &key, &key_len, 1);
+  assert(status == MEMCACHED_SUCCESS);
+
+  memcached_result_create(memc, &result_obj);
+  result= memcached_fetch_result(memc, &result_obj, &status);
+
+  assert(result);
+  assert(status == MEMCACHED_SUCCESS);
+
+  return 0;
+}
+
 #include "ketama_test_cases.h"
 test_return user_supplied_bug18(memcached_st *trash)
 {
@@ -3022,7 +3057,7 @@ test_st user_tests[] ={
   {"user_supplied_bug8", 1, user_supplied_bug8 },
   {"user_supplied_bug9", 1, user_supplied_bug9 },
   {"user_supplied_bug10", 1, user_supplied_bug10 },
-//  {"user_supplied_bug11", 1, user_supplied_bug11 },
+  {"user_supplied_bug11", 1, user_supplied_bug11 },
   {"user_supplied_bug12", 1, user_supplied_bug12 },
   {"user_supplied_bug13", 1, user_supplied_bug13 },
   {"user_supplied_bug14", 1, user_supplied_bug14 },
@@ -3031,6 +3066,7 @@ test_st user_tests[] ={
   {"user_supplied_bug17", 1, user_supplied_bug17 },
   {"user_supplied_bug18", 1, user_supplied_bug18 },
   {"user_supplied_bug19", 1, user_supplied_bug19 },
+  {"user_supplied_bug20", 1, user_supplied_bug20 },
   {0, 0, 0}
 };